Method of grooving mine hoist drums and the like



Nov, 9, 1965 w. E. RUEHMER 3,216,293

METHOD OF GROOVING MINE HOIST DRUMS AND THE LIKE Filed Jan. 22, 1962 7 Sheets-Sheet l INVENTOR.

Nov. 9, 1965 w. E. RUEHMER 3,216,293

METHOD OF GROOVING MINE HOIST DRUMS AND THE LIKE Filed Jan. 22, 1962 7 Sheets-Sheet 2 IN VENTGR.

Nov. 9, 1965 w. E. RUEHMER METHOD OF GROOVING MINE HOIST DRUMS AND THE LIKE Filed Jan. 22, 1962 7 Sheets-Sheet 5 Nov. 9, 1965 w. E. RUEHMER 3,216,293

METHOD OF GHOOVING MINE HOIST DRUMS AND THE LIKE Filed Jan. 22, 1962 '7 Sheets-Sheet 4 INVENTOR.

Nov. 9, 1965 w. E. RUEHMER 3,216,293

METHOD OF GROOVING MINE HOIST DRUMS AND THE LIKE Filed Jan. 22, 1962 7 Sheets-Sheet 5 INVENTOR.

Nov. 9, 1965 w. E. RUEHMER 3,216,293

METHOD 0E GRoovING MINE HoIsT DRUMS AMD THE LIKE Filed Jan. 22, 1962 7 Sheets-Sheet 6 INVENTOR Nov. 9, 1965 W. E. RUEHMER METHOD oF GROOVING MINE HoIsT DRUMS AND THE LIKE Filed Jan. 22, 1962 7 Sheets-Sheet 7 INVENTOR.

United States Patent O 3,216,293 METHOD F GROOVING MINE HOIST DRUMS AND THE LIKE Walter E. Ruehmer, South Milwaukee, Wis., assignor to Nordberg Manufacturing Company, Milwaukee', Wis.,

a corporation 'of Wisconsin Filed Jan. 22, 1962, Ser. No. 167,790 S Claims. (Cl. 82-1) This invention relates to a method and apparatus for `grooving cable winding drums, for example mine hoist drums.

A primary purpose of the invention is a method and apparatus of the type described which forms a crossover between adjacent parallel grooves on the periphery `of a mine hoist drum or the like.

Another purpose is a method and apparatus of the type described having improved means for controlling the Ioperation of the grooving tool.

Other purposes will .appear in the ensuing specification, drawings and claims.

The :invention is illustrated diagrammat-ically in the following drawings wherein:

FIGURE 1 is a front perspective view of the assembly for grooving mine hoist drums or the like,

FIGURE 2 is an enlarged perspective of the apparatus for controlling vthe movement of the grooving tool,

FIGURE 3 is a side view 4of the control apparatus shown in `FIGURE 2,

-FIGURE 4 is a top plan view of the control apparatus shown in FIGURES 2 and 3,

FIGURE 5 is an enlarged front view .of the grooving tool and associated control equipment,

FIGURE 6 is a perspective showin-g a drum to be grooved in position on a rotating platform, .and

FIGURE 7 is a wiring diagram of the control circuit used.

This invention is particularly concerned with grooving large mine hoist drums. One of the problems in the formation of such grooves is to provide crossover points so that the cable positioned in the grooves may cross over from one groove 4to the next. The present invention proposes a system for automatically and periodically forming crossover grooves .as the grooving tool works on the periphery of the drum.

In FIGURE l, a pair of posts or columns 10 may be suitably mounted on a base or oor 12. A rotating platform or tab-le 14 which mounts or supports the drum D during the grooving operation is positioned between the posts and is driven by a suitable motor or the like, not shown, Mounted on the post-s 10 is a crossrail 16 which may be arranged for vertical movement on the posts. A horizontal support 18 may be lmounted between the upper end of the posts to stabilize the equipment.

Mounted for horizontal movement on the lcrossrail 16 -is a saddle 20, at the right-hand side of FIGURE 1, which mounts the grooving tool. At the left-hand side of FIG- URE 1 is .a similar saddle 22 which is used to balance the dru-m being grooved. The saddle 22 does not .have the contr-ol equipment that is on the saddle 20, but does have a stabilizing block or the like 22a, at its lower end, which bears against the drum being grooved at a point opposite the grooving t-ool. In this way, the pressure on `opposite sides of the drum is equal and there will be no inaccuracies in the grooves being formed. The saddles 2G .and 22 may be moved .horizontally by means of a screw 23 counterweighted by a cable connection 24 or the like which passes about pulleys 26 positioned on arms 28 on either side of the crossrail 16. Pulleys or the like 29 may be suitably mounted on each of the .saddles for connection to the cable 24.

Mounted at the bottom of the saddle 20 is a suit-able grooving tool 30. As shown 4in FIGURES 5 and 6, the tool 30, which may be any one of a number of conventional grooving t-ools, forms grooves 32 about `the periphery 34 of a cable winding drum. The tool 30 will be held in a stationary verti-cal position during .a major portion 4of the drum rotation. The `grooves for-med by the tool when in this positi-on will be generally horizontal, or perpendicular to the drum axis, and will be parallel to one another. These grooves are indicated at 36 in FIG- URE 5.

In order to form crossover grooves so that the cable may pass from one parallel groove to the next, the tool 30 wil-l be indexed downward or upwardly as the drum rotates. The crossover grooves, which are somewhat helical, are indicated at 38 in FIGURE 5. There may be one, two or more crossover grooves during each 360 deg-rees of groove, the number of crossover grooves depending upon the size of the drum and the diameter of the cable. As `shown in the drawings, there are two crossover grooves, one `each 180 degrees. Accordingly, the tool 30 will move downward a distance slightly more than half the width of the groove during each indexing operation. The .tool 30 will lmove downward a distance equal to .the width of the groove plus the space between grooves during each 360 degrees of drum rotation.

In order to provide the proper timing for the indexing movement, a cam surface 40, shown in FIGURES 1 .and 6, may be positioned on the periphery of .the platform or table 14. The number of camming surfaces depends upon t-he number of crossover grooves during each 360 degrees of groove. A follower or contact 42 is positioned to contact the camming surface 40. Movement of the follower 42 will close a limit switch or the like, shown in FIGURE 7, to actuate the indexing mechanism. The indexing operation will be stopped when the tool has been moved a .predetermined distance downward. The means for stopping the tool will be described hereinafter.

A ram 44 may be -mounted on the saddle 20 for verti-cal movement and carries t-he tool y30 at its lower end. A similar .ram 46 may be mounted on the saddle 22. A suitable drive motor 48, preferably continuously running vduring the grooving operation, is mounted on a housing or the like 50. The ram `44 moves Within the housing 50 `and is reciprocated by a drive gear 52, shown in FIG- URES 4 and 5. The drive gear 52 .is controlled by the motor 48, through the gear, clutch and brake arrangement to be described.

The motor 48 drives a shaft 54, shown in FIGURES 2 and 3. The shaft 54 runs at right angles to the motor drive shaft and there may be suitable gearing S6 or the like. At the outer end of the drive shaft 54 is a drive gear 58 which is in mesh with an outer idler gear 60. Mounted on the same shaft with the outer idler gear 60 is an inner idler gear 62 which is in mesh with a driven gear 64. Each of the idler gears 60 and 62 is mounted on an arm 66 which rotates about the axis of the driven gear 64. A suitable plate 68, which may be in the shape of a segment, has a groove 70 which may be used to move the arm 66 to any desired angular position. A conventional nut and bolt connection 72 may be used to lock the arm in position. By having a pivotal arm which mounts the idler gears, it is possible to use different size drive gears and so to change the speed at which the ram and tool move vertically.

The driven gear 64 is mounted on a suitable shaft 74 which is connected to a clutch 76. The shaft 74 may run through a suitable bearing housing or the like 78. The clutch may be electrical and is activated by the cam arrangement on the periphery of the table 14. A shaft extends outwardly from the clutch 76 and passes through a gear box 82. On the outward end of the shaft 80 is a suitable electrical brake 84. The brake 84 is operated when the clutch 76 is disengaged to provide instantaneousstopping of the ram once the tool 30 has traveled a sufficient downward distance. In this way, there will be no overtravel and the tool will stop as soon as the crossover groove has been completely formed. The gear box 82 may include a conventional arrangement for transferring the rotation of shaft 80 to drive gear 52. The drive gear 52 is in mesh with a gear rack 83 on the ram and is used to move the ram in a vertical direction.

The upper end of the ram 44 may mount a suitable bracket 86 which carries a vertical indexing bar 88. A suitable bracket or guide 90 may be mounted on the housing 50 to stabilize the lower end of the bar 88. Mounted along one side of the bar 88 are a series of generally equally spaced teeth or projections or buttons 92. The distance between the points of each of the teeth is the distance which the ram should travel when moving the tool 30 through one indexing operation. A suitable limit switch 94 having a cam 96 is positioned to bear against the teeth 92. The limit switch 94, as will be explained hereinafter, is effective to stop the downward movement of the rarn and tool 30 by simultaneously activating the brake 84 and disengaging the clutch 76. The cam 96 will bear against the teeth 92 and movement of the indexing shaft 88 downward a distance equal to the space between teeth will cause the limit switch 94 to stop the ram. In this way, the downward movement of the tool 30 can be precisely controlled.

FIGURE 7 illustrates the electrical circuit used in controlling the brake and clutch. Power to operate the brake and clutch may come from a suitable source to a transformer indicated generally at 98, if a step down is necessary. One side of the transformer secondary is connected through a fuse to a three-position switch 100. The switch 100 adapts the system for automatic or manual operation. When switch 100 is in the auto position, the off and auto terminals are connected together. The various components making the electrical circuit may easiest be described by going through a sequence of operation. Considering first when indexing is to be done manually, the switch 100 is turned to the hand position. When switch 102 is closed by the operator, power is directed from the transformer 98 through the switch 100 to the clutch 76 and to brake relay coil 84a of the brake 84. The brake is normally holding through brake contacts 84b which are released when brake relay coil 84a is activated. The clutch will close and the ram will start downward. The ram is stopped by releasing switch 102. The clutch may be conventional and, accordingly, it is not thought necessary to describe its circuit in detail.

When the selector switch 100 is on auto the operation is as follows. As the ram is stationary, one of the buttons 92 will open the top contact of switch 94 and close the bottom contact. Light 108 will thus be energized. The table or platform 14 is turning and when follower 42 contacts the camming surface 40,.both contacts of switch 104 will close. The top contact of switch 104 energizes clutch 76 and opens brake contacts 8411 through its relay coil 84a. The bottom contact of .switch 104 operates light 106. The initial movement of the ram permits switch 94 to move to the position shown in FIG- URE 7 which cuts out light 108.

After the camming surface 40 has moved by follower 42, switch 104 opens. The circuit to the brake and clutch is still complete however, through the top contact of switch 94. Light 106 is now extinguished. The ram is stopped when the next ram button engages switch 94 and moves its contacts opposite to that shown in FIGURE 7. The clutch and brake are opened and light 108 is lit.

The ram is started by the follower 42 vstriking the camming surface 40. It is stopped by the buttons 92. In this way the vertical distance the ram moves is precisely controlled and will not be changed by varying table speed. The buttons can be pre-set so that there will be the proper, number of crossovers on each drum. The start of each crossover will be aligned, but the end may vary slightly due to a change in table speed. The important point is that all of the grooves will be placed on the drum.

In addition to the indexing operation controls, it is necessary to have motor controls to position the ram prior to the beginning of a grooving operation. Line is connected directly to the transformer 98 and to a pushbutton 112 which will stop the motor 48 when it is pressed. In circuit with the push-button 112 are push-buttons 114 and 116, which are in parallel. Push-button 114 is effective to run the motor 48 in a direction to move the ram upward whereas button 116 is effective to move Vthe ram downward. The motor control circuits are separate and apart from the circuits controlling the movement of the ram. The push buttons 114 and 116 are effective to operate the magnetic starter for the motor 48. The starter has not been shown as it is a conventional circuit. Push buttons 114 and 116 are principally concerned with controlling the direction of motor travel and ram movement.

Coil 120 in series with push button 114 is effective, through contacts 122, to lock in ram movement in an up direction. When coil 120 is energized, by operation of push button 114, contacts 124 will open so that push button 116 is ineffective. In like manner, coil 126, through contacts 128, is effective to lock in down movement of the ram. Contacts are controlled by coil 126 to open the circuit to push button 114. Contacts 132 are opened by an overload. When it is desired to have automatic ram movement in a down direction, push button 116 is operated. Push button 114 is operated when it is desired to have automatic ram movement in an up direction. These 1same push buttons may be used to position the ram prior to the beginning of a grooving operation.

The use, operation and function of the invention are as follows:

It is necessary to provide crossover points in the grooves on the periphery of a mine hoist drum or the like so that the cable in the grooves will lie smooth and flat and there will be no ridges which could eventually cause wear. The present invention proposes at least one crossover point for each 360 degrees of groove circumference. The crossover points are formed during the grooving operation by indexing the grooving tool downward or upward as the drum continues to rotate. The grooving tool will move through a predetermined distance so that the crossover g-roove has a proper length. The number of crossover points in each 360 degrees of drum circumference may vary, but the total length of the crossovers for each 360 degrees should be slightly greater than the width of the groove. The major portion of the groove in each 360 degrees will be generally perpendicular to the drum axis, with the crossover grooves forming slightly helical connections between adjacent parallel grooves.

Because -of the size of the drum D, it is preferred to groove half of the drum first. The grooving tool is moved downward as described'until the top half of the drum is grooved. Then the drum is turned over and the grooving tool moves up to groove what is now the top half. This second step is shown in FIGURE 6. In the alternative, the grooving operation may begin at the middle of the drum. If the grooving tool went down through the com- I plete height of the drum, there may be inaccuracies in the grooves.

In order to provide crossover points at predetermined locations, it is proposed to provide a cam arrangement on the side of the table supporting the drum to be grooved. When the cam 42 strikes the camming surface 40, a limit switch is closed and the ram and grooving tool start downward. The ram will continue downward until the limit switch 94 has been closed. This switch will close after the ram has moved through a predetermined vertical distance.

The first limit switch activates a clutch which couples a continuously running motor with the ram-drive arrangement. Upon activation of the clutch, the ram will start its downward movement. The clutch will be deactivated after the ram has moved a distance sufficient to close limit switch 94. Brake 84 is operated simultaneously with the clutch. The brake normally holds and is released when the clutch is ope-rated. In this Way, there will be no overrun and the crossover `groove will be formed to precise tolerances. The combination of the brake and clutch is important to precisely and immediately stop the ram after it has moved a sufiicient distance to form the crossover groove.

Whereas the preferred form of the invention has been shown and described herein, it should be realized that there are many modifications, substitutions, and alterations thereto within the scope of the following claims.

I claim:

1. A method of grooving the periphery of a cable winding drum with a grooving tool, including the steps of positioning said tool `for grooving the drum, rotating the drum relative to the tool to form a groove which is generally perpendicular to the drum axis, coupling said tool to a continuously running d-rive means at least once in each complete revolution of the drum and as said drum rotates to move the tool generally parallel to the drum axis to form at least one defined somewhat helically directed groove portion in each 360 degrees of groove, uncoupling the tool fro-m the drive means and simultaneously applying a braking force to the tool after movement of the grooving tool parallel to the drum axis in one complete revolution of the drum is at least equal to the width of the groove being formed, thereafter repeating said successive steps until the periphery of the drum has a single continuous groove, major portions of which in each 360 degrees are parallel to each other.

2. The method of claim 1 further characterized in that said tool moves in a direction parallel to the drum axis twice during each revolution of the drum, With the total of said two axial movements being at least equal to the width of said groove.

3. The method of claim 1 further characterized in that each of said defined helical portions start and stop at approximately the same circumferential position on the drum periphery.

4. A method of grooving the periphery of a cable winding drum with a grooving tool, including the steps of positioning said tool for grooving the drum, rotating the drum relative to the tool to form a groove which is generally perpendicular to the drum axis, coupling said tool to a continuously running drive means at least once in each complete revolution of the drum and as said drum rotates to move the tool, generally parallel to the drum axis to form at least one defined somewhat helically directed groove portion in each 360 degrees of groove, uncoupling the tool from the drive means and simultaneously applying a braking force to the tool after movement of the grooving tool parallel to the drum axis in one complete revolution of the drum is at least equal to the width of the groove being formed, repeating said successive steps until approximately half of the drum has a single continuous groove, major portions of which in each 360 degrees are parallel to each other, turning the drum over, and then repeating the grooving steps, but in the opposite direction, until said groove is continuous over generally the entire periphery of the idrum.

5. The method of clai-m 4 further characterized in that said grooving tool is first moved from the top of the drum down to approximately the center of the drum and is then moved Ifrom the center back to the top.

References Cited by the Examiner UNITED STATES PATENTS 2,237,744 4/41 Mullen 82-1 2,268,983 1/42 Gilmore et al. 82-1 2,620,996 12/52 Le Bus 82-5 X 2,734,695 2/56 Le Bus 82-5 X 3,043,172 7/ 62 Colebrook 82-2 3,057,234 10/62 Heer 82-2 X OTHER REFERENCES American Machinist, vol. 90, January 31, 1946, Intermittent Leadscrew, page 117 (copy in Group 340).

WILLIAM W. DYER, IR., Primary Examiner. 

1. A METHOD OF GROOVING THE PERIPHERY OF A CABLE WINDING DRUM WITH A GROOVING TOOL, INCLUDING THE STEPS OF POSITIONING SAID TOOL FOR GROOVING THE DRUM, ROTATING THE DRUM RELATIVE TO THE TOOL TO FORM A GROOVE WHICH IS GENERALLY PERPENDICULAR TO THE DRUM AXIS, COUPLING SAID TOOL TO A CONTINUOUSLY RUNNING DRIVE MEANS AT LEAST ONCE IN EACH COMPLETE REVOLUTION OF THE DRUM AND AS SAID DRUM ROTATES TO MOVE THE TOOL GENERALLY PARALLEL TO THE DRUM AXIS TO FORM AT LEAST ONE DEFINED SOMEWHAT HELICALLY DIRECTED GROOVE PORTION IN EACH 360 DEGREES OF GROOVE, UNCOUPLING THE TOOL FROM THE DRIVE MEANS AND SIMULTANEOUSLY APPLYING A BRAKING FORCE TO THE TOOL AFTER MOVEMENT OF THE GROOVING TOOL PARALLEL TO THE DRUM AXIS IN ONE COMPLETE REVOLUTION OF THE DRUM IS AT LEAST EQUAL TO THE WIDTH OF THE GROOVE BEING FORMED, THEREAFTER REPEATING SAID SUCCESSIVE STEPS UNTIL THE PERIPHERY OF THE DRUM HAS A SINGLE CONTINUOUS GROOVE, MAJOR PORTIONS OF WHICH IN EACH 360 DEGREES ARE PARALLEL TO EACH OTHER. 